Preparation of beta-amino acids

A process for the biocatalytic production of a β-amino acid precursor, comprising:

• reacting at least one substrate of the general formula (I)
• wherein R1 and R2 independently from each other are selected from:
• hydrogen;
• a linear or branched, optionally substituted, lower alkyl group;
• a linear or branched, optionally substituted, lower alkenyl group;
• an optionally substituted cyclic alkyl group;
• a mono- or polycyclic, optionally substituted aryl group;
• a mono- or polycyclic, optionally substituted heteroaryl group;
• a linear or branched, optionally substituted alkoxy group;
• an amino group;
• a linear or branched, optionally substituted alkylamino group;
• a linear or branched, optionally substituted alkylthio group;
• a linear or branched, optionally substituted acyl group,
• a carboxyl group or
• an aldehyde group;
• said substrate being present in stereoisomerically pure form or as a mixture of stereoisomers, wherein the stereoisomerically pure form or the mixture of stereoisomers may optionally be a salt,
• in the presence of at least one enzyme, catalyzing the hydrolytic cleavage of a hydantoin and/or dihydropyrimidin ring,
• so that a β-amino acid precursor of the general formula (II)
• wherein R1 and R2 are identified as above,
• is produced;
• said process being characterized in that the at least one enzyme which is applied in said process is obtained from Vigna angularis and/or which comprises at least one partial sequence having an identity of between 60 percent and 100 percent to at least one of the following partial sequences:
• ITGPEGQRLAGP
• (SEQ ID NO:
• 7)
• EEIARARKSGQRVIGEPVAS.
• (SEQ ID NO:
• 5)

Hydantoinase, containing at least one of the following partial sequences:

• ITGPEGQRLAGP
• (SEQ ID NO:
• 7)
• EEIARARKSGQRVIGEPVAS.
• (SEQ ID NO:
• 5)

Hydantoinase, obtained by preparing a crude extract of cell material from an organism, and subjecting said crude extract to the sequential purification steps of

• a) ion exchange chromatography
• b) hydrophobic chromatography
• c) gel filtration
• d) affinity chromatography
• e) anion exchange
• f) gel filtration.